As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ORD INFLIGHT T1184/15FEB - CREW REPORTED SMOKE IN CABIN AND COCKPIT. RETURNED TO ORD AND LANDED WITHOUT INCIDENT. ACCOMPLISHED BURN OUT OF HIGH PRESSURE PNEUMATIC DUCTING AND CHANGED COALESCER BAGS. SYSTEM GROUND CHECKED NORMAL OPERATION.